Loading floors that are easily retooled are equipped with seating or mounting rails extending lengthwise in the loading floor. Special locking devices are used for securing pieces of freight with a latching hook which is mounted in a frame that in turn is securable in a releasable manner to the above mentioned rails in the floor. Seats are secured to the same rail by screws or clamps.
German Patent Publication (DE-PS) 3,107,745 (Engel et al.), published on Sep. 16, 1982, discloses a locking mechanism for freight loading systems. The known locking mechanism functions as a so-called YZ-latch. A YZ-latch is capable to hold a piece of freight, such as a pallet or container in its loaded condition in the cargo hold in the vertical y-direction, as well as in the lateral z-direction, and to fix the load in the loaded position. For this purpose, such mechanisms are equipped with a latching hook which reaches over a respective projection of the piece of freight such as a pallet or container of standardized dimensions.
Commercial aircraft which are equipped with large freight loading gates to provide access even to the upper deck, are capable of transporting relatively bulky goods. Such goods include, for example, complete propulsion plants which are mounted on a pallet with only a portion of the outer fairing or cowling removed. For transporting such goods, it is especially important that these pieces of freight once inside the aircraft body, do not come into contact with the aircraft body. This is especially important, because damage to the aircraft body and/or to the piece of freight could have serious consequences.
Especially in connection with very long pieces of freight which do not fit crosswise through the freight loading gate so as to be aligned with the longitudinal aircraft axis, it is necessary to move these long pieces initially lengthwise through the loading gate perpendicularly to the longitudinal aircraft axis, and to then rotate such pieces inside the aircraft next to the loading gate by about 90.degree.. In order to perform such rotation, it is necessary to take special safety precautions. These precautions must prevent that a piece of freight does not contact the aircraft body wall opposite of the freight loading gate. German Patent Publication DE 3,102,146 (Engel et al.), published on Sep. 2, 1982, discloses a mechanism for turning freight pallets in order to accomplish, for example, the above mentioned 90.degree. rotation of a large freight piece. This known device comprises a journal or pivoting pin arranged in the area of the freight loading door in the aircraft loading floor. Hardware forming part of a pallet is constructed for cooperation with the journal or pivoting pin. The just mentioned hardware is so positioned on the pallet that it is intended to automatically engage the journal or pivoting pin to thereby cause the rotation of the pallet, for example, by 90.degree..